This category features JTAG In-Circuit Debuggers for Atmel AVR and ATmega FLASH microcontrollers. In-Circuit Debuggers are low-cost development tools providing real-time emulation for all AVR and ATmega microcontrollers with built-in JTAG interface.

Please read this to save you lots of grief and wasted time: There are two versions of the Atmel AVR JTAGICE in-circuit debugger (ICD):

Atmel JTAGICE

Atmel JTAGICE mkII

The JTAGICE was the initial version released by Atmel. It only supports JTAG in-circuit debugging/programming for a very limited number of AVR microcontrollers — see the Atmel Studio software release notes for a full list. The majority of third-party clones on the market is only compatible to the JTAGICE with the same limitations. Last time we checked, Atmel Studio supported the following micros with the JTAGICE: ATmega16, ATmega16L, ATmega162, ATmega162L, ATmega169, ATmega169L, ATmega32, ATmega32L, ATmega323, ATmega323L, ATmega64, ATmega64L, ATmega128, ATmega128L, AT90CAN128 (with limitations), AT90CAN128L (with limitations).

The JTAGICE mkII is Atmel's successor to the original JTAGICE. The JTAGICE mkII model supports all AVR microcontrollers.

The mkII also adds several features that the older JTAGICE did not have: It supports debugging and programming via DebugWire, which is used by all the smaller pincount AVRs. In addition, it integrates an ISP programmer, so the unit can also be connected to boards that have only an ISP interface and be used as a programmer. With that, the mkII is really three units in one: A JTAG in-circuit debugger and programmer, a DebugWire debugger/programmer and an ISP programmer.

A cheaper alternative to the JTAGICE mkII is the AVR-DRAGON, which we offer below. It doesn't support PDI mode for many Xmega devices, but otherwise is compatible only it does not come enclosed so requires more care to use.